Large trucks must not use the far left lanes when there are many lanes. You will notice that the transport trucks that have to take I-285 also stay in the right two lanes of 285.

HOV(High Occupancy Vehicle) Lanes are available for buses, carpools with two or more people, and motorcycles. They are marked with a diamond and are on the far left side of the roadway. They have broken lines for entrance and exit points.

In some places the minimum speed is 40 and the speed limit is 55 but if you are going to go that slowly you should stay in the rightmost lane.